Objectives: Candida glabrata is becoming one of the most prevalent pathogenic yeasts in cases of oral diseases. Mucositis is an recurrent oral infection in immunocompromised patients, and the actual guidelines recommend the use of fluconazole (Flu) for many cases. However, the azole resistance by C. glabrata is renowned, causing a reduced therapeutic response, especially when it occurs in biofilms. In this study, we performed an in vitro evaluation of an alternative pharmacotherapy for C. glabrata biofilm infections, combining ascorbic acid (AA) with Flu. AA is recognized for degrading -glucans, an important compound of the biofilm matrices, which prevent drug diffusion. Materials and Methods: Thus, routine clinical 30 or 40mg/l doses of Flu were applied to C. glabrata biofilms simultaneously with 200 or 300mg/l of AA. Results: The results showed that this combination effectively promoted the degradation of the biofilm network, but unfortunately, also stimulated the growth of the yeasts population due to release of several glucose monomers during -glucans hydrolysis. Conclusions: As a result, it was proven that, contrary to what happens in treatment of bacterial infection, AA should not be used together with Flu in the treatment of oral mucositis caused by Candida.The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This work was supported by the Programa Operacional, Fatores de competitividade – COMPETE and by national funds through FCT – Fundação para a Ciência e a Tecnologia on the scope of the projects FCT PTDC/SAU-MIC/119069/2010, RECI/EBBEBI/0179/2012 and PEst-OE/EQB/LA0023/2013 and Célia F. Rodrigues’ SFRH/BD/93078/2013 PhD grant
